There's was a lot of hubbub when some U.S. government loans to green energy companies went bust, but there's also been notable successes. Electric vehicle (EV) maker Tesla, a loan recipient, is proving to be another exception, so much so that it is reimbursing taxpayers years ahead of schedule.

Today, Detroit Free Press's Alan Ohnsman reported that the U.S. government had approved a revised repayment schedule with the electric automaker. The amended terms of the loan allow Tesla to accelerate payments to pay off the entire balance by 2017. Tesla received US$465 million from the U.S. Energy Department to fund the development and creation of its EV designs, which are now hitting the market.

The article noted that Tesla is not yet profitable, but anticipates that it will be by the end of this quarter. The company had a net loss higher than previous years at the end of 2012, mainly because it was building up its inventory in anticipation of scaling up for future sales. However, other EV makers including Coda and Fisker automotive have hit troubled times, and success is not guaranteed.

Tesla has embraced a unique sales model that sells vehicles directly out of retail stores and "galleries" instead of dealerships. Customers browse its latest models, make reservations to buy, or in some instances, take a test drive. Automobile Magazine named Tesla's Model S automobile of the year after it took a spin.

"We weren't expecting much from the Tesla other than some interesting dinner conversation as we considered "real" candidates like the Subaru BRZ and the Porsche Boxster," its editors wrote, noting that the Model S outperformed gasoline-powered cars.

Pike Research has estimated that EV sales will hit 3.8 million worldwide by 2020 even as consumer interest wanes. Could Tesla's financial performance keep pace with its success on the test track?